max raid devices via initrd with FC3

[DJ Delorie]

In case anyone else ran into this...

I spend a day or two debugging a non-booting machine, only to find out
that the tools in initrd (FC3, x86-64) only support 16 raid devices.
Since the vg with root included md16 and higher, I couldn't boot.
Root is now on its own raid0 (md5) to keep initrd happy.

Yes, I'm planning on upgrading, but before this change I couldn't get
the fc6 disks to recognize my pre-existing installation, so I couldn't
just upgrade.